Development of sensorimotor integration in children

描述（由申请人提供）：本研究计划的总体长期目标是了解内部模型或表征的发展，这些模型或表征是感觉运动行为的基础。以前的研究表明，所谓的感觉运动内部模型，或地图，是控制目标导向运动的基础。这些映射可以被概念化为以眼为中心（用于视觉）或以头为中心（用于听觉）的坐标框架到控制效应器的神经命令的计算变换，例如以手为中心的坐标。迄今为止，关于感觉运动地图的发展及其相互作用的研究还很缺乏。具体目标1是确定动觉-运动或触觉-运动内部表征（模态内条件）的发展特征。具体目标2是确定5至10岁儿童的动觉-视觉-运动或触觉-视觉-运动内部表征（联运条件）的发展。不同模态的内部模型相互作用的神经基础建议在后顶叶皮层，神经元已被证明编码视觉和听觉信号，并将它们映射到以手为中心的坐标。这些实验将允许确定内和跨模态运动地图分化的特点，并获得这些特点的发展景观。PI假设：（1）在幼儿中，模态内运动表征的调谐范围非常广泛，导致相当大的表现变异性;（2）随着年龄的增长，这些内部表征变得更好地“调谐”;（3）在联运环境中，定义不太明确的（模态内）感觉运动表征更容易受到定义更好的内部模型的影响。这是支持的初步结果显示较强的视觉运动适应条件后，幼儿比年龄较大的儿童，谁可能有更好的调整内模态感觉运动模型的运动后效。这项工作的总体意义在于解决两个知识差距，这两个差距阻碍了更好地了解感觉运动表征如何在儿童中发展和相互作用。理解这一点是未来发展性运动障碍（如发展性协调障碍（DCD））的重要基础。

DESCRIPTION (provided by applicant): The overall long-term objective of this research program is to understand the development of internal models or representations that underlie sensorimotor behavior. Previous research suggests that so-called sensorimotor internal models, or maps, are the basis for the control of target-directed movements. These maps can be conceptualized as computational transformations of eye- (for vision) or head-centered (for audition) coordinate frames to neural commands controlling the effector e.g. in hand-centered coordinates. To date, studies about the development of sensorimotor maps, and their interactions are lacking. Specific aim 1 is to determine the characteristics of the development of either kinesthetic-motor or auditory-motor internal representations (intramodal condition). Specific aim 2 is to determine the development of either kinesthetic-visuo-motor or auditory-visuo-motor internal representations (intermodal condition) in 5 to 10 year old children. A neural basis for interactions of internal models of different modalities is suggested in the posterior parietal cortex, where neurons have been shown to code both visual and auditory signals and map them onto hand-centered coordinates. These experiments will allow determination of the characteristics of intra- and intermodal motor map differentiation, and to obtain a developmental landscape of these characteristics. The PIs hypothesize that (1) intramodal motor representations are very broadly tuned in young children, resulting in considerable performance variability; (2) with increasing age, these internal representations become better 'tuned'; and (3) in intermodal contexts the less well-defined (intramodal) sensorimotor representations are more susceptible to being affected by better defined internal models. This is supported by preliminary results showing stronger auditory-motor aftereffects after a visuo-motor adaptation condition in young children than in older children, who are likely to have better-tuned intramodal sensorimotor models. The overall significance of the work proposed lies in addressing two knowledge gaps that stand in the way of having better insights into how sensorimotor representations develop and interact in children. Understanding this is an essential foundation for future work on developmental motor impairments such as developmental coordination disorder (DCD).